This proposal is to seek support for acquisition of an ABI377 automated DNA sequencer to be shared by 13 investigators at Cold Spring Harbor Laboratory (CSHL), whose areas of research cover-plant genetics, cancer, and neurobiology. These 13 major users are situated in three nearby buildings on the CSHL campus, Beckman, James/Sambrook, and Delbruck/Page, and currently have no automated DNA sequencer available. The instrument will be housed in the CSHL Cancer Center Nucleic Acid Research Shared Resource Facility in the Beckman building. This location ensures ease of access to all of the major users of the instrument. An internal advisory committee will ensure equitable use of the instrument. DNA sequencing is essential to the studies of all the participating investigators and represents a large fraction of their total research effort. All of the studies involve molecular analyses in which DNA sequencing is vital. An automated DNA sequencer will greatly aid in these endeavors. The NCRR provides an ideal mechanism to fund the purchase of an automated DNA sequencer and to provide for sharing among investigators such that its use is optimized.